Ablative techniques and their mechanisms of action
| Localized treatment modalities | Principle of action |
|---|---|
| Percutaneous ethanol injection (PEI) | Instillation of ethanol directly into the tumor causing cellular dehydration, protein denaturation, and occlusion of small vessels resulting in coagulation necrosis |
| Radiofrequency ablation (RFA) | Application of oscillating electrical currents resulting in resistive heating surrounding an electrode and tissue hyperthermia |
| Microwave ablation (MW) | Direct application of a propagating microwave energy level electromagnetic field to induce tissue hyperthermia via dielectric hysteresis |
| Irreversible electroporation (IRE) | Alteration of transmembrane potentials to induce irreversible disruption of cell membrane integrity |
| Percutaneous laser ablation (PLA) | Deposition of laser light via fiberoptic applicators to induce tissue hyperthermia |
| Cryoablation | Changes in gas pressures result in cooling of a cryoprobe in direct thermal contact with tumor resulting in ice crystal formation and osmotic shock |
| Stereotactic body radiation therapy (SBRT) High-intensity focused ultrasound (HIFU) | Extracorporeal coordinate system localization (+/- internal fiducial guidance) delivering multiple noncoplanar beams of photon beam radiation in a limited number of treatment fractions. This results in tumor cell death via direct DNA damage, as well as indirect DNA and cell damage through free radical formation Extracorporeal coordinate system focusing of multiple ultrasound beams into a focal point resulting in tissue hyperthermia and mechanical cavitation |